Dual-Phase Immunomodulation by the Bovine β-Casein Peptide KEMPFPK: Insights into Potential TLR Interaction and Gut Microbiota-Mediated Effects

TL;DR

This study shows that the KEMPFPK peptide from cow milk can modulate the immune system and gut bacteria, offering potential for functional foods.

Contribution

The study reveals KEMPFPK's dual-phase immunomodulation via TLR interaction and gut microbiota modulation.

Findings

KEMPFPK enhances macrophage activity and reduces inflammation via NF-κB and MAPK inhibition.

KEMPFPK binds to TLR2 and TLR4, suggesting a direct mechanism for immune modulation.

KEMPFPK restores immune function in mice and reshapes gut microbiota by promoting beneficial bacteria.

Abstract

This study investigates the immunomodulatory effects and underlying mechanisms of KEMPFPK, a peptide derived from bovine β-casein, using integrated in vitro, in silico, and in vivo approaches. In RAW264.7 macrophages, KEMPFPK enhanced proliferation, phagocytosis, and migration and selectively upregulated the chemokine MCP-1. Under LPS-induced inflammation, KEMPFPK suppressed pro-inflammatory cytokines (IL-1β, TNF-α) and NO production while promoting the anti-inflammatory cytokine IL-10. These effects were mediated through the inhibition of NF-κB and MAPK signaling pathways. Molecular docking predicted high-affinity binding of KEMPFPK to Toll-like receptors (TLR2 and TLR4), suggesting a potential mechanism for its immunomodulatory activity. In cyclophosphamide (CTX)-induced immunosuppressed mice, KEMPFPK administration restored immune organ indices, rebalanced serum cytokine levels, and modulated humoral immunity. Importantly, KEMPFPK was associated with a significantly reshaped gut microbiota profile, characterized by the promotion of beneficial genera (e.g., Ligilactobacillus, Adlercreutzia) and the suppression of opportunistic pathogens (e.g., Escherichia–Shigella). These findings establish KEMPFPK as a dual-phase immunomodulator and suggest that its effects may involve direct immune cell regulation coupled with indirect microbiota remodeling. This study provides a scientific foundation for the application of KEMPFPK in immunomodulatory functional foods.

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